PC lent et qui s'éteint tout seul

Bonjour,

J'ai un PC portable COMPAQ R4000. IL s'éteint tout seul et rame dès que je lance plusieurs choses en même temps.
IL ne s'est rallumé qu'au bout de 5 ou 6 tentatives et s'éteignait dès le démarrage Windows meme en mode sans echec.

J'ai fait un scan Avast et spyware mais rien. Je colle le rapport hijackthis :
Logfile of Trend Micro HijackThis v2.0.2
Scan saved at 14:26:15, on 12/04/2008
Platform: Windows XP SP2 (WinNT 5.01.2600)
MSIE: Internet Explorer v6.00 SP2 (6.00.2900.2180)
Boot mode: Normal

Running processes:
C:\WINDOWS\System32\smss.exe
C:\WINDOWS\system32\winlogon.exe
C:\WINDOWS\system32\services.exe
C:\WINDOWS\system32\lsass.exe
C:\WINDOWS\system32\Ati2evxx.exe
C:\WINDOWS\system32\svchost.exe
C:\WINDOWS\System32\svchost.exe
C:\Program Files\Alwil Software\Avast4\aswUpdSv.exe
C:\Program Files\Alwil Software\Avast4\ashServ.exe
C:\WINDOWS\system32\spoolsv.exe
C:\WINDOWS\system32\Ati2evxx.exe
C:\WINDOWS\Explorer.EXE
C:\Program Files\Fichiers communs\LightScribe\LSSrvc.exe
C:\Program Files\Fichiers communs\Microsoft Shared\VS7Debug\mdm.exe
C:\Program Files\MioNet\MioNetManager.exe
C:\WINDOWS\system32\svchost.exe
C:\Program Files\MioNet\jvm\bin\MioNet.exe
C:\Program Files\FBM Software\ZeroSpyware\ZeroSpyware.exe
C:\Program Files\Alwil Software\Avast4\ashMaiSv.exe
C:\Program Files\Alwil Software\Avast4\ashWebSv.exe
C:\Program Files\ATI Technologies\ATI Control Panel\atiptaxx.exe
C:\Program Files\hpq\HP Wireless Assistant\HP Wireless Assistant.exe
C:\Program Files\HP\HP Software Update\HPWuSchd2.exe
C:\Program Files\Synaptics\SynTP\SynTPLpr.exe
C:\Program Files\Synaptics\SynTP\SynTPEnh.exe
C:\Program Files\QuickTime\qttask.exe
C:\Program Files\HPQ\Quick Launch Buttons\EabServr.exe
C:\Program Files\BroadJump\Client Foundation\CFD.exe
C:\Program Files\HPQ\SHARED\HPQWMI.exe
C:\Program Files\Fichiers communs\InstallShield\UpdateService\issch.exe
C:\PROGRA~1\ALWILS~1\Avast4\ashDisp.exe
C:\WINDOWS\VM_STI.EXE
C:\Program Files\Java\jre1.6.0_05\bin\jusched.exe
C:\WINDOWS\system32\ctfmon.exe
C:\Program Files\Google\GoogleToolbarNotifier\GoogleToolbarNotifier.exe
C:\Program Files\Windows Live\Messenger\MsnMsgr.Exe
C:\Program Files\Hp\Digital Imaging\bin\hpqtra08.exe
C:\Program Files\Philips\Philips SPC210NC Webcam\TrayMin210.exe
C:\Program Files\HP\Digital Imaging\bin\hpqimzone.exe
C:\Program Files\HP\Digital Imaging\bin\hpqSTE08.exe
C:\WINDOWS\system32\RunDll32.exe
C:\Program Files\Mozilla Firefox\firefox.exe
C:\Program Files\Lavalys\EVEREST Ultimate Edition\everest.exe
C:\Documents and Settings\LECENDRIER Gaëlle\Bureau\HiJackThis.exe

R0 - HKCU\Software\Microsoft\Internet Explorer\Main,Start Page = https://www.google.fr/?gws_rd=ssl
R1 - HKLM\Software\Microsoft\Internet Explorer\Main,Default_Page_URL = https://www.msn.com/fr-fr?cobrand=compaq-notebook.msn.com&ocid=HPDHP&pc=CPNTDF
R1 - HKCU\Software\Microsoft\Internet Explorer\Main,Window Title = Windows Internet Explorer fourni par Yahoo! France
R0 - HKCU\Software\Microsoft\Internet Explorer\Toolbar,LinksFolderName = Liens
R3 - URLSearchHook: Yahoo! Toolbar - {EF99BD32-C1FB-11D2-892F-0090271D4F88} - C:\Program Files\Yahoo!\Companion\Installs\cpn1\yt.dll
O2 - BHO: Yahoo! Toolbar Helper - {02478D38-C3F9-4EFB-9B51-7695ECA05670} - C:\Program Files\Yahoo!\Companion\Installs\cpn1\yt.dll
O2 - BHO: Adobe PDF Reader Link Helper - {06849E9F-C8D7-4D59-B87D-784B7D6BE0B3} - C:\Program Files\Adobe\Acrobat 7.0\ActiveX\AcroIEHelper.dll
O2 - BHO: SSVHelper Class - {761497BB-D6F0-462C-B6EB-D4DAF1D92D43} - C:\Program Files\Java\jre1.6.0_05\bin\ssv.dll
O2 - BHO: Programme d'aide de l'Assistant de connexion Windows Live - {9030D464-4C02-4ABF-8ECC-5164760863C6} - C:\Program Files\Fichiers communs\Microsoft Shared\Windows Live\WindowsLiveLogin.dll
O2 - BHO: Google Toolbar Helper - {AA58ED58-01DD-4d91-8333-CF10577473F7} - c:\program files\google\googletoolbar1.dll
O3 - Toolbar: Yahoo! Toolbar - {EF99BD32-C1FB-11D2-892F-0090271D4F88} - C:\Program Files\Yahoo!\Companion\Installs\cpn1\yt.dll
O3 - Toolbar: &Google - {2318C2B1-4965-11d4-9B18-009027A5CD4F} - c:\program files\google\googletoolbar1.dll
O4 - HKLM\..\Run: [avast!] C:\PROGRA~1\ALWILS~1\Avast4\ashDisp.exe
O4 - HKLM\..\Run: [MSConfig] C:\WINDOWS\PCHealth\HelpCtr\Binaries\MSConfig.exe /auto
O4 - HKLM\..\RunOnce: [ZeroSpyware] "C:\Program Files\FBM Software\ZeroSpyware\ZSLoader.exe" -STARTUP
O4 - HKCU\..\Run: [CTFMON.EXE] C:\WINDOWS\system32\ctfmon.exe
O4 - HKUS\S-1-5-19\..\Run: [CTFMON.EXE] C:\WINDOWS\system32\CTFMON.EXE (User 'SERVICE LOCAL')
O4 - HKUS\S-1-5-20\..\Run: [CTFMON.EXE] C:\WINDOWS\system32\CTFMON.EXE (User 'SERVICE RÉSEAU')
O4 - HKUS\S-1-5-18\..\Run: [CTFMON.EXE] C:\WINDOWS\system32\CTFMON.EXE (User 'SYSTEM')
O4 - HKUS\.DEFAULT\..\Run: [CTFMON.EXE] C:\WINDOWS\system32\CTFMON.EXE (User 'Default user')
O4 - Global Startup: Microsoft Office.lnk = C:\Program Files\Microsoft Office\Office10\OSA.EXE
O8 - Extra context menu item: E&xporter vers Microsoft Excel - res://C:\PROGRA~1\MICROS~3\Office12\EXCEL.EXE/3000
O9 - Extra button: (no name) - {08B0E5C0-4FCB-11CF-AAA5-00401C608501} - C:\Program Files\Java\jre1.6.0_05\bin\ssv.dll
O9 - Extra 'Tools' menuitem: Console Java (Sun) - {08B0E5C0-4FCB-11CF-AAA5-00401C608501} - C:\Program Files\Java\jre1.6.0_05\bin\ssv.dll
O9 - Extra button: Research - {92780B25-18CC-41C8-B9BE-3C9C571A8263} - C:\PROGRA~1\MICROS~3\Office12\REFIEBAR.DLL
O9 - Extra button: (no name) - {e2e2dd38-d088-4134-82b7-f2ba38496583} - C:\WINDOWS\Network Diagnostic\xpnetdiag.exe
O9 - Extra 'Tools' menuitem: @xpsp3res.dll,-20001 - {e2e2dd38-d088-4134-82b7-f2ba38496583} - C:\WINDOWS\Network Diagnostic\xpnetdiag.exe
O9 - Extra button: Messenger - {FB5F1910-F110-11d2-BB9E-00C04F795683} - C:\Program Files\Messenger\msmsgs.exe
O9 - Extra 'Tools' menuitem: Windows Messenger - {FB5F1910-F110-11d2-BB9E-00C04F795683} - C:\Program Files\Messenger\msmsgs.exe
O10 - Unknown file in Winsock LSP: c:\windows\system32\nwprovau.dll
O14 - IERESET.INF: START_PAGE_URL=https://www.msn.com/fr-fr?cobrand=compaq-notebook.msn.com&ocid=HPDHP&pc=CPNTDF
O16 - DPF: {17492023-C23A-453E-A040-C7C580BBF700} (Windows Genuine Advantage Validation Tool) - http://download.microsoft.com/download/E/5/6/E5611B10-0D6D-4117-8430-A67417AA88CD/LegitCheckControl.cab
O16 - DPF: {4F1E5B1A-2A80-42CA-8532-2D05CB959537} (MSN Photo Upload Tool) - http://gfx1.hotmail.com/mail/w2/pr02/resources/MSNPUpld.cab
O16 - DPF: {5C051655-FCD5-4969-9182-770EA5AA5565} (Solitaire Showdown Class) - http://messenger.zone.msn.com/binary/SolitaireShowdown.cab56986.cab
O16 - DPF: {C3F79A2B-B9B4-4A66-B012-3EE46475B072} (MessengerStatsClient Class) - http://messenger.zone.msn.com/binary/MessengerStatsPAClient.cab56907.cab
O23 - Service: avast! iAVS4 Control Service (aswUpdSv) - ALWIL Software - C:\Program Files\Alwil Software\Avast4\aswUpdSv.exe
O23 - Service: Ati HotKey Poller - ATI Technologies Inc. - C:\WINDOWS\system32\Ati2evxx.exe
O23 - Service: avast! Antivirus - ALWIL Software - C:\Program Files\Alwil Software\Avast4\ashServ.exe
O23 - Service: avast! Mail Scanner - ALWIL Software - C:\Program Files\Alwil Software\Avast4\ashMaiSv.exe
O23 - Service: avast! Web Scanner - ALWIL Software - C:\Program Files\Alwil Software\Avast4\ashWebSv.exe
O23 - Service: Boonty Games - BOONTY - C:\Program Files\Fichiers communs\BOONTY Shared\Service\Boonty.exe
O23 - Service: HP WMI Interface (hpqwmi) - Hewlett-Packard Development Company, L.P. - C:\Program Files\HPQ\SHARED\HPQWMI.exe
O23 - Service: LightScribeService Direct Disc Labeling Service (LightScribeService) - Unknown owner - C:\Program Files\Fichiers communs\LightScribe\LSSrvc.exe
O23 - Service: MioNet Service (MioNet) - Unknown owner - C:\Program Files\MioNet\MioNetManager.exe
O23 - Service: Pml Driver HPZ12 - HP - C:\WINDOWS\system32\HPZipm12.exe

J'ai aussi fait un gros nettoyage pour le demarrage car plein de choses se lançaient. Autre chose, le processus affiche plein de trucs meme quand je n'ai rien lancer !

Merci beaucoup !